Global water resources assessment under climatic change in.pdfVIP

Water Resources Systems—Water availability and global change (Proceedings of symposium HS02a held 1 during IUGG2003 at Sapporo, July 2003). IAHS Publ. no. 280, 2003. Global water resources assessment under climatic change in 2050 using TRIP TAIKAN OKI Research Institute for Humanity and Nature, Kyoto 602-0878, Japan taikan@iis.u-tokyo.ac.jp YASUSHI AGATA, SHINJIRO KANAE, TAKAO SARUHASHI KATUMI MUSIAKE Institute of Industrial Science, Univ. of Tokyo, Tokyo 153-8505, Japan Abstract Annual water availability was derived from annual runoff estimated by land surface models using Total Runoff Integrating Pathways (TRIP) with 0.5° × 0.5° longitude/latitude resolution globally. Global distribution of water withdrawal for each sector in the same horizontal spatial resolution was estimated based on country-base statistics. Based on the framework, future projections of the global water resources considering population growth, climatic change, and the increase of water consumption per capita were carried out. Change in annual runoff was estimated based on the climatic simulation by a general circulation model coupled with TRIP. With the increase of population only, future population under strong water scarcity, when water scarcity index is larger than 0.4, will increase by 90% in 2050 compared to the current situation in 1995. Consideration